Using SharePoint 2013 Federated Search with an OpenSearch connection, and the response has multiple extention fields (which are processed by custom Search Display Template. Unfortunately, depending upon data returned, receive an error of "Microsoft.Office.Server.Search.Query.Pipeline.Connectors.OpenSearchReaderConnector : Response length exceeded maximum length" which appears to be only 64k (while the response returned is 124177 bytes).

Entry from log file:

09/02/2015 12:21:54.06 NodeRunnerQuery1-3b80be33-d85d- (0x43BC) 0x4228 Search                         Query Processing               aizfj Unexpected Microsoft.Office.Server.Search.Query.Pipeline.Connectors.OpenSearchReaderConnector : Response length exceeded maximum length: [url=https://spus001sha50.russellreynolds.com:9090/api/opensearch/rrakman?searchterms=boston&startindex=0&count=10], [MaximumResponseLength=64] System.Net.WebException: Response length exceeded maximum length: [url=https://spus001sha50.russellreynolds.com:9090/api/opensearch/rrakman?searchterms=boston&startindex=0&count=10], [MaximumResponseLength=64], [ReceivedResponseLength=124177 bytes]     at Microsoft.Office.Server.Search.Query.Pipeline.Connectors.OpenSearchReaderConnector.GetXmlFromUrl(String url) a2102a9d-50a6-7094-e886-e908470b912d

Hi,

Please check this below

http://www.wikiguga.com/topic/19d8abee991a17211416f6f1a441cfcf

Hi,

It is a by design issue in SharePoint that the error would occur when the number of results is high in a result source with OpenSearch.

When we set the value to a higher number, it will also cause issues.

Here is a similar thread for your reference:

https://social.msdn.microsoft.com/Forums/sharepoint/en-US/b5c2c4f9-c027-443c-b1b5-29de79f7cb35/sharepoint-2013-search-result-source-?forum=sharepointsearch

Best regards,

Victoria